Allow admin to edit additional minutes in UI

Problem to solve

Currently, additional minutes can be edited via API. It would be nice to be able to edit it through the UI as well.

Intended users

Internal users, primarily Support

Proposal

Provide field in top-level group admin edit screen to allow editing of additional minutes.

Permissions and Security

• Expected impact to Admin

Documentation

Availability & Testing

What does success look like, and how can we measure that?

Relevant team members can change additional minutes through the UI instead of API.

Links / references

Currently done through console or chatops.